1. Field of the Invention
This invention concerns disposable sanitary napkins. As used herein, sanitary napkins are considered to be absorbent devices designed to be worn externally of the body by woven, usually during their menstrual periods, and to receive and contain menses and other vaginal discharges. Disposable sanitary napkins are intended to be disgarded after use and soiling rather than being cleaned and reused.
2. Background Art
Disposable sanitary napkins are staple items of modern society. In their simplest form they comprise an absorbent element interposed between a pervious body contacting element and an impervious protective barrier. The absorbent element is, of course, intended to receive and contain menses and other vaginal discharges. The body-containing element (sometimes called a topsheet or an overwrap) is intended to provide more or less comfortable and dry-feeling contact with body surfaces while allowing free passage of fluids therethrough into the absorbent element. The protective barrier is intended to prevent menses or other vaginal discharges which are expelled or which escape from the absorbent element from soiling the user's garments.
In addition to the three functional elements mentioned above, disposable sanitary napkins are generally provided with means for supporting the device adjacent the user's crotch area, even as the user moves, where it can most effectively perform its intended function. Traditionally, this support means has involved the use of waist encircling belts having suspenders depending from the front and rear thereof. These suspenders are of various designs and are provided with means of various designs for securing the sanitary napkins thereto.
More recently, sanitary napkins have been provided with adhesive attachment means for securing the device to the inner crotch area of the user's undergarments. Elimination of the traditional belt is generally considered to be a definite advance in sanitary napkin technology.
Usually, sanitary napkins are unitary structures of generally rectangular or oval shape having a greater or lesser thickness depending on the particular design. U.S. Pat. Nos. 595,861, 2,625,161, and 3,111,948, for example, illustrate conventional types of sanitary napkins.
As noted, the usual sanitary napkin presents the appearance of and performs as a unitary (i.e. one piece) device. While certain sanitary napkin designs involve two absorbent elements (as described in, for example, U.S. Pat. No. 2,965,102 issued to Harwood on Dec. 20, 1960) or two separable units (as described in, for example, U.S. Pat. No. 2,683,457 issued to Cunningham on July 13, 1954), they perform as unitary devices.
While previously known sanitary napkins do perform their intended function, each conventional design suffers from certain deficiencies in one or more of absorbency of body fluids, protection of the user's garments from soiling, and physical comfort to the user.
One species of sanitary napkin which has gained popularity in recent times is sometimes referred to as a mini-pad or panty shield. These particular devices are generally no more than conventional sanitary napkins in which the bulk and, therefore, the fluid capacity of the absorbent element has been drastically reduced as compared to conventional sanitary napkins. They are usually provided with adhesive attachment means. Such devices are generally perceived by the user as having enhanced wearing comfort, but their drastically reduced absorbent capacity makes them useful only when menstrual flows are small an impractical for use throughout the menstrual cycle.